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1.
本对于全局优化问题提出一个改进的进化规划算法,该算法以概率p接收基于电磁理论求出合力方向作为随机搜索方向,以概率1-p接收按正态分布产生的随机搜索方向。改进算法不仅克服了传统进化规划算法随机搜索的盲目性,而且保留了传统进化规划算法全局搜索性。本算法应用于几个典型例题,数值结果表明本算法是可行的,有效的。  相似文献   

2.
设计了一种新颖的基于差分进化算法和NSGA-Ⅱ的混合进化算法用来解决多目标优化问题。在此算法中,根据算法的搜索情况设计相应的自适应变异算子,以便在突变操作中找到Pareto解。同时,选择操作将基于NSGA-Ⅱ快速非优超排序和拥挤机制将父代与子代的双种群进行截短,确保最优解不会丢失并保证解的多样性。三个经典测试函数的仿真结果表明,文中算法在实现多目标优化问题的两个目标(获得收敛于真实Pareto前沿的解和解沿着前沿均匀扩展)方面表现出良好的综合性能。  相似文献   

3.
针对多目标优化问题,设计一种基于量子计算和非支配排序遗传算法相结合的智能算法进行求解,综合量子算法和非支配排序遗传算法的优点,在局部搜索和全局搜索之间进行权衡。混合算法采用量子比特对问题的解进行编码,基于量子旋转门算子、分散交叉算子以及高斯变异算子对种群进行更新。进行局部深入搜索时,用一个解在目标空间中跟理想点的距离来评价该解的优劣;进行全局搜索时,基于非支配排序遗传算法中的有效前沿的划分和解之间的拥挤距离来评价某个解。最后,在经典的测试函数ZDT5上对所提混合算法进行了测试。通过对比分析若干项针对有效解集的评价指标,该混合算法在跟最优有效前沿的逼近程度以及有效解集分布的均匀程度上均优于目前得到广泛应用的非支配排序遗传算法。  相似文献   

4.
在模糊C均值(Fuzzy C-Means,FCM)聚类应用过程中,针对目前模糊加权指数的确定缺乏理论依据和有效评价方法这一问题,提出了一种基于子集测度的模糊加权指数计算方法.首先根据子集测度理论定义了一个聚类有效性函数,然后依据该函数在聚类过程中通过循环进化迭代来计算聚类结果的有效性,并将其值反馈到模糊加权指数m的变化中,而使m收敛到一个稳定解,即得到最佳模糊加权指数.理论分析和实验表明,该算法是有效的,为模糊加权指数m的探讨研究提供了一种新的思路和途径.  相似文献   

5.
一种新的交通网络设计优化算法   总被引:1,自引:2,他引:1  
交通网络设计问题是研究如何用定量的方法在已有交通网络上添加或扩容某些路段的问题.文章在回顾交通网络设计问题文献的基础上,提出了基于图论网络优化思想的解决该类问题的一种新思路,给出了启发式算法,并进行了算法复杂性分析,最后通过算例验证了其有效性.  相似文献   

6.
一种改进的进化规划算法及其收敛性   总被引:16,自引:0,他引:16  
1 引 言进化算法是一类借鉴生物界自然选择和自然遗传机制的随机搜索算法 ,主要包括遗传算法 ( genetic algorithms,GA)、进化规划 ( evolutionary programming,EP)和进化策略( evolution strategies,ES) [1 ] .遗传算法 ,进化策略和进化规划分别由 J.H.Holland,I.Rechenberg和 L.J.Fogel提出[2 ,3,4] .这些算法有许多相似性 ,且近年来都被应用于实值连续函数全局优化问题 ,并取得了较好的效果 .一些学者对进化算法的收敛性进行了分析[5,6,7,8] ,但总的说来 ,有关进化算法的理论研究成果目前还不是很多 ,尤其是进化规划和进化策略几…  相似文献   

7.
针对目标函数估值昂贵的多目标优化问题,提出了基于聚类的代理辅助进化算法。在MOEA/D算法的框架下,对种群进行聚类,并通过权重向量的邻域选出种群子集,在子集上使用径向基插值函数辅助的差分进化算法得到新解,对种群进行更新。在7个DTLZ标准测试问题上进行了数值实验,计算结果表明本文提出的算法比新近提出的多目标邻域回归优化(MONRO)算法具有优势。  相似文献   

8.
针对在处理约束优化问题时约束条件难以处理的问题,提出了一种求解约束优化问题的改进差分进化算法.即在每代进化前将群体分为可行个体和不可行个体两类,对不可行个体,用差量法将其逐个转化为可行个体,并保持种群规模不变,经过一序列的进化后,计算所有可行个体的适应度并找到问题的最优解.对5个经典函数进行了优化测试,测试结果表明提出的算法对求解约束优化问题是有效的.  相似文献   

9.
一种改进的遗传k-means聚类算法   总被引:8,自引:0,他引:8  
在经典的k-means聚类算法中,聚类数k必须事先给定,然而在现实中k很难被精确的确定.本文提出了一种改进的遗传k-means聚类算法,并构造了一个用来评价分类程度好坏的适应度函数,该适应度函数考虑的是在提高紧凑度(类内距)和分离度(类间距)的同时使得分类个数尽可能少.最后采用两个人工数据集和三个UCI数据集对k-means聚类算法(KM),遗传聚类算法(GA),遗传k-means聚类算法(GKM)和改进的遗传k-means聚类算法(IGKM)进行比较研究,比较的指标有类间距、类内距和分类正确率.研究证明改进的遗传k-means算法能够自动获取最佳聚类数k并且保持较高的正确率.  相似文献   

10.
一种稳健的聚类方法   总被引:5,自引:0,他引:5  
本文讨论一种新的聚类方法 :属性均值聚类 .通过理论分析 ,属性均值聚类是比模糊均值聚类更稳健的聚类方法 .数值实验说明了该方法的有效性  相似文献   

11.
This paper presents a hybrid heuristic-triangle evolution (TE) for global optimization. It is a real coded evolutionary algorithm. As in differential evolution (DE), TE targets each individual in current population and attempts to replace it by a new better individual. However, the way of generating new individuals is different. TE generates new individuals in a Nelder- Mead way, while the simplices used in TE is 1 or 2 dimensional. The proposed algorithm is very easy to use and efficient for global optimization problems with continuous variables. Moreover, it requires only one (explicit) control parameter. Numerical results show that the new algorithm is comparable with DE for low dimensional problems but it outperforms DE for high dimensional problems.  相似文献   

12.
An important class of deterministic methods for global optimization is based on the theory of terminal attractors and repellers. Unfortunately, the utilization of scalar repellers is unsuitable, when the dimension n of the problem assumes values of operational interest. In previous papers the author et al. showed that BFSG-type methods, approximating the Hessian of twice continuously differentiable functions with a structured matrix, are very efficient to compute local minima, particularly in the secant case. On the other hand, the algorithms founded on the classical αBB technique are often ineffective for computational reasons. In order to increase the power of repellers in the tunneling phases, the utilization of repeller matrices with a proper structure is certainly promising and deserves investigation. In this work, it is shown that a BFGS-type method of low complexity, implemented in the local optimizations, can be effectively matched with proper repeller matrices in the tunneling phases. The novel algorithm FBαBB, which can be applied in the frame of the αBB computational scheme, is very efficient in terms of Number of Functions Generations (NFG), Success Rates (SR) in the evaluation of the global minimum and Number of Local Searches (NLS).  相似文献   

13.
We present an algorithm for finding a global minimum of a multimodal,multivariate function whose evaluation is very expensive, affected by noise andwhose derivatives are not available. The proposed algorithm is a new version ofthe well known Price's algorithm and its distinguishing feature is that ittries to employ as much as possible the information about the objectivefunction obtained at previous iterates. The algorithm has been tested on alarge set of standard test problems and it has shown a satisfactorycomputational behaviour. The proposed algorithm has been used to solveefficiently some difficult optimization problems deriving from the study ofeclipsing binary star light curves.  相似文献   

14.
基于凹性割的线性双层规划全局优化算法   总被引:1,自引:0,他引:1  
通过对线性双层规划下层问题对偶间隙的讨论,定义了一种凹性割,利用该凹性割的性质,给出了一个求解线性双层规划的割平面算法。由于线性双层规划全局最优解可在其约束域的极点上达到,提出的算法能求得问题的全局最优解,并通过一个算例说明了算法的有效性。  相似文献   

15.
This paper introduces a novel global optimization heuristic algorithm based on the basic paradigms of Evolutionary Algorithms (EA). The algorithm greatly extends a previous strategy proposed by the authors in Munteanu and Lazarescu (1998). In the newly designed algorithm the exploration/exploitation of the search space is adapted on-line based on the current features of the landscape that is being searched. The on-line adaptation mechanism involves a decision process as to whether more exploitation or exploration is needed depending on the current progress of the algorithm and on the current estimated potential of discovering better solutions. The convergence with probability 1 in finite time and discrete space is analyzed, as well as an extensive comparison with other evolutionary optimization heuristics is performed on a set of test functions.  相似文献   

16.
A Taxonomy of Evolutionary Algorithms in Combinatorial Optimization   总被引:1,自引:0,他引:1  
This paper shows how evolutionary algorithms can be described in a concise, yet comprehensive and accurate way. A classification scheme is introduced and presented in a tabular form called TEA (Table of Evolutionary Algorithms). It distinguishes between different classes of evolutionary algorithms (e.g., genetic algorithms, ant systems) by enumerating the fundamental ingredients of each of these algorithms. At the end, possible uses of the TEA are illustrated on classical evolutionary algorithms.  相似文献   

17.
A Dual-Objective Evolutionary Algorithm for Rules Extraction in Data Mining   总被引:1,自引:0,他引:1  
This paper presents a dual-objective evolutionary algorithm (DOEA) for extracting multiple decision rule lists in data mining, which aims at satisfying the classification criteria of high accuracy and ease of user comprehension. Unlike existing approaches, the algorithm incorporates the concept of Pareto dominance to evolve a set of non-dominated decision rule lists each having different classification accuracy and number of rules over a specified range. The classification results of DOEA are analyzed and compared with existing rule-based and non-rule based classifiers based upon 8 test problems obtained from UCI Machine Learning Repository. It is shown that the DOEA produces comprehensible rules with competitive classification accuracy as compared to many methods in literature. Results obtained from box plots and t-tests further examine its invariance to random partition of datasets. An erratum to this article is available at .  相似文献   

18.
本基于一种新的全局优化算法(EM),提出一种求解模糊优化问题的全局优化算法。针对三维水平井轨道设计问题,提出两个模糊模型。最后把算法及模型应用到实际问题中,数值结果表明算法及模型是有效的、正确的。  相似文献   

19.
We consider the global minimization of a bound-constrained function with a so-called funnel structure. We develop a two-phase procedure that uses sampling, local optimization, and Gaussian smoothing to construct a smooth model of the underlying funnel. The procedure is embedded in a trust-region framework that avoids the pitfalls of a fixed sampling radius. We present a numerical comparison to three popular methods and show that the new algorithm is robust and uses up to 20 times fewer local minimizations steps.  相似文献   

20.
针对约束优化问题,提出了一类将种群中的个体分类排序的思想.算法的特点在于:先将种群中的解分为可行解和不可行解两类,然后分别按照不同的标准排序.由于很多约束优化问题的最优解位于可行域的边界上或附近,所以排序时并不认为可行解一定优于不可行解.基于此分类排队思想,特别设计了只允许同等级个体进行交叉的新的交叉算子,称之为同等级交叉算子,以及基于一维搜索的变异算子.算法同时采用了保证固定比例不可行解的自适应策略.4个标准测试函数的数值仿真结果验证了算法的有效性.  相似文献   

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